Black hat SEO is procedure that tries to achieve high rankings in short time by using various SEO techniques that don't follow search engine guidelines, or treated as means of deception. One black hat technique uses text that is hidden, either as text colored similar to the background, in an invisible div, or positioned off screen.

White hat SEO is Called as ethical SEO, it follows search engines guidelines. In this a content page that the search engine indexes and subsequently ranks, would contain the same content that a visitor would see.